A few things to be aware of. You should read the stickies at the top of the amps forum, first and foremost. After that, carefully examine your needs, and remember the bulk of your budget should be for the speaker cab or cabs.

If you like your tone(s), you could sell your combo and pick up a Fender Rumble 350 head new for $290, and pick up a couple of Fender 410 cabs. You could leave one at the practice site and one for practice at home, and take them both when you need both for gigs. If you get 410 cabs, I would get "matching" Fender Neo or Fender Rumble cabs. The Neo cabs are lighter.

I'm in the process of doing just this, only I'm waiting for the Rumble 500 head (may be available in a month?). There are used Fender Neo and Rumble cabs on GC used, and they have a 30 day return period if there are issues.